A display of an electronic device such as a smart phone or a tablet Personal Computer (PC) typically includes a screen display device, which visually displays data, and the use of a touch screen equipped with a touch panel is also known.
According to the general conventional display technology, an entirety of the display of the electronic device is turned on or off according to a user's control or turned on when a particular event is generated in the electronic device and an alarm of the generated event is displayed in a predetermined area. Further, a technology for turning on some areas of the display when the electronic device is equipped with an auxiliary device such as a cover has been already developed.